Human activities releasing greenhouse gases (GHGs) http://unfccc.int/cop3/fccc/climate/fact22.htm
Human activities releasing greenhouse gases (GHGs) http://unfccc.int/cop3/fccc/climate/fact22.htm
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Most important human activities emit greenhouse gases (GHGs). Emissions started to rise
dramatically in the 1800s due to the Industrial Revolution and changes in land use. Many
greenhouse-gas-emitting activities are now essential to the global economy and a fundamental
part of modern life.
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Most important human activities emit greenhouse gases (GHGs). Emissions started to rise
dramatically in the 1800s due to the Industrial Revolution and changes in land use. Many
greenhouse-gas-emitting activities are now essential to the global economy and a fundamental
part of modern life.
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Carbon dioxide from the burning of fossil fuels is the largest single source of greenhouse
gas emissions from human activities. The supply and use of fossil fuels accounts for about
three quarters of mankind's carbon dioxide (CO2) emissions (equal to some 5.9 billion metric
tonnes of carbon in 1992), one-fifth of the methane (CH4), and a significant quantity of nitrous
oxide (N2O). It also produces nitrogen oxides (NOx), hydrocarbons (HCs), and carbon monoxide
(CO), which, though not greenhouse gases themselves, influence chemical cycles in the
atmosphere that create or destroy other greenhouse gases, such as tropospheric ozone.
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Carbon dioxide from the burning of fossil fuels is the largest single source of greenhouse
gas emissions from human activities. The supply and use of fossil fuels accounts for about
three quarters of mankind's carbon dioxide (CO2) emissions (equal to some 5.9 billion metric
tonnes of carbon in 1992), one-fifth of the methane (CH4), and a significant quantity of nitrous
oxide (N2O). It also produces nitrogen oxides (NOx), hydrocarbons (HCs), and carbon monoxide
(CO), which, though not greenhouse gases themselves, influence chemical cycles in the
atmosphere that create or destroy other greenhouse gases, such as tropospheric ozone.
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Most emissions associated with energy use result when fossil fuels are burned. Oil, natural
gas, and coal (which emits the most carbon per unit of energy supplied) furnish most of the
energy used to produce electricity, run automobiles, heat houses, and power factories.
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Most emissions associated with energy use result when fossil fuels are burned. Oil, natural
gas, and coal (which emits the most carbon per unit of energy supplied) furnish most of the
energy used to produce electricity, run automobiles, heat houses, and power factories.
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Extracting, processing, transporting, and distributing fossil fuels also releases greenhouse
gases. These releases can be deliberate, as when natural gas is flared or vented from oil wells,
emitting mostly carbon dioxide and methane, respectively. They can also result from accidents,
poor maintenance, and small leaks in well heads, pipe fittings, and pipelines.
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Extracting, processing, transporting, and distributing fossil fuels also releases greenhouse
gases. These releases can be deliberate, as when natural gas is flared or vented from oil wells,
emitting mostly carbon dioxide and methane, respectively. They can also result from accidents,
poor maintenance, and small leaks in well heads, pipe fittings, and pipelines.
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Deforestation is the second largest source of carbon dioxide. When forests are cleared for
agriculture or development, most of the carbon in the burned or decomposing trees escapes to the
atmosphere.
Producing lime (calcium oxide) to make cement accounts for 2.5% of CO 2 emissions from
industrial sources.
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Deforestation is the second largest source of carbon dioxide. When forests are cleared for
agriculture or development, most of the carbon in the burned or decomposing trees escapes to the
atmosphere.
Producing lime (calcium oxide) to make cement accounts for 2.5% of CO2 emissions from
industrial sources.
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Domesticated animals emit methane. The second-most important greenhouse gas after carbon
dioxide, methane is produced by cattle, dairy cows, buffalo, goats, sheep, camels, pigs, and
horses.
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Domesticated animals emit methane. The second-most important greenhouse gas after carbon
dioxide, methane is produced by cattle, dairy cows, buffalo, goats, sheep, camels, pigs, and
horses.
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Rice cultivation also releases methane . . . "Wetland" or "paddy" rice farming produces
roughly one-fifth to one-quarter of global methane emissions from human activities. Accounting
for over 90 percent of all rice production, wetland rice is grown in fields that are flooded or
irrigated for much of the growing season. Bacteria and other micro-organisms in the soil of the
flooded rice paddy decompose organic matter and produce methane.
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Rice cultivation also releases methane . . . "Wetland" or "paddy" rice farming produces
roughly one-fifth to one-quarter of global methane emissions from human activities. Accounting
for over 90 percent of all rice production, wetland rice is grown in fields that are flooded or
irrigated for much of the growing season. Bacteria and other micro-organisms in the soil of the
flooded rice paddy decompose organic matter and produce methane.
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. . . as does the disposal and treatment of garbage and human wastes. When garbage is
buried in a landfill, it sooner or later undergoes anaerobic (oxygen-free) decomposition and
emits methane (and some carbon dioxide). Unless the gas is captured and used as a fuel, the
methane eventually escapes to the atmosphere.
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. . . as does the disposal and treatment of garbage and human wastes. When garbage is
buried in a landfill, it sooner or later undergoes anaerobic (oxygen-free) decomposition and
emits methane (and some carbon dioxide). Unless the gas is captured and used as a fuel, the
methane eventually escapes to the atmosphere.
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Fertilizer use increases nitrous oxide emissions. The nitrogen contained in many fertilizers
enhances the natural processes of nitrification and denitrification that are carried out by bacteria
and other microbes in the soil. These processes convert some nitrogen into nitrous oxide.
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Fertilizer use increases nitrous oxide emissions. The nitrogen contained in many fertilizers
enhances the natural processes of nitrification and denitrification that are carried out by bacteria
and other microbes in the soil. These processes convert some nitrogen into nitrous oxide.
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Industry creates chlorofluorocarbons (CFCs) and other halocarbons for use in various
products and industrial processes.
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Industry creates chlorofluorocarbons (CFCs) and other halocarbons for use in various
products and industrial processes.
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